Mapping the terrain over a given route for construction repair, and other civil engineering projects have long been practiced both in the United States and abroad using conventional methods of surveying and installation of monuments. This a time consuming and very expensive task. Current estimates to perform these surveys is approximately $12,000 per mile. Those large areas of terrain without existing highways, the cost per mile of surveying non-existing roads or monuments can be substantially higher. For example, new highways must be built in western Europe and in the former Soviet Union which may require very expensive surveying projects. Precise positional data is mandatory for highway surveys as it is critical to locate all terrain features (natural and manmade) which will affect the cost and schedule of highway repair and construction. Accuracy standards exist for such surveys which require X, Y and Z accuracy to within fractions of a foot.
In recent years the United States has established a series of satellites in the Global Positioning System (GPS) as a method of providing location of the surface of the earth in XYZ to a certain accuracy. The purpose of the GPS is to allow a person with the GPS receiver to determine his location anywhere that the receiver can receive signals from the GPS satellites. At the present time, the accuracy of position determination from the GPS standard civilian GPS receiver is approximately one meter. This accuracy is not sufficient for highway mapping which requires accuracies of 0.4 feet or 12 centimeters.
Various technologies have been used for determining precise position. Measurement from aerial photography with subsequent photogrammetric data reduction has long been in existence. With the implementation of the GPS several inventors have used this system for a variety of position determination purposes. For example, U.S. Pat. No. 5,087,919 to Odagawa et al. describes an on-board navigation apparatus which uses input from the global positioning system. U.S. Pat. No. 4,837,700 to Ando et al. describes a method and apparatus for processing data in a GPS receiving device in a road vehicle. This is an attempt to determine the vehicle position generally, by virtue of the GPS. Similarly, U.S. Pat. No. 5,111,209 to Toriyama describes a satellite based position determining system for determining the position of a mobile station using communication satellites.
An extension of the position determination using satellites, is represented by U.S. Pat. No. 5,144,318 to Kishi wherein a GPS receive station is located in a vehicle and whereby the vehicle can navigate a preplanned path by virtue of the information it receives from the GPS. U.S. Pat. No. 5,210,540 to Masumoto shows yet other enhancements for determining position of a vehicle by virtue of an on-board GPS receiver.
Other methods for determining a location of earth by virtue of satellites have also been described using an interaction with a stored mapping system. One such system is described in U.S. Pat. No. 5,214,757 to Mauney et al. and U.S. Pat. No. 4,839,656 to O'Neil et al.
In addition to the above, other surveying data and height measurements have been made using GPS. U.S. Pat. No. 5,030,957 to Evans describes a method of simultaneously measuring orthometric and geometric heights using the GPS satellite system.
All of these above references use the GPS but in a fashion not giving the required accuracy for various civil engineering projects when used on a moving vehicle. In addition, none of these GPS related programs document images that are taken simultaneously to further depict man-made and natural terrain features which are necessary in the civil engineering process.
In marked contrast to the above, the present invention uses a series of camera systems together with a GPS positioning system and a dead reckoning system to precisely calculate the location of the surveying vehicle at any point in time thereby correlating images taken with the geodetic position of the vehicle at the time images are taken.